Apparatus for heating by steam



May 9, 1961 J. E. THOMPSON APPARATUS FOR HEATING BY STEAM Filed Dec. 11,1957 STEAM INVENTOR .J ()HN E.THOMPSON W, awmmwm ATTORNEYS gatented May9, 1961 United States PatentO summer are a tm IS the. which apsg's aneven heating f t kettle 2.98am. a

John E. Drive, Flossmoor, Ill.

.1 i Filed Dec;- 11,1957, Set; -N0; 702,017 1' claim. (on amt-4invention relatesto a stea heating systo provide steam heat with variousge' equipment, such as, steam kettles steam adiatorsj'etc, I l I I 1 inv s'tam'has 'gerierallyheen used as asource heat' fgr industrial anddomestic purposes. Theprinoinal is dvan hood t steam u p essure producesasurfa'c'e' that is too -hot for' many purposes. This had led toover-heating and produces hot spots in industrial heating equipment,such as steam kettles.

It is the general object of the present invention to provide a systemwhich is generally inexpensive to construct and does not require specialequipment.

' It is an object of the present invention to provide steam heatingequipment which may be operated from ambient temperatures to 230 F.

It is also an object of the present invention to operate a steam heatingsystem under positive flow control.

It is a still further object of the present invention to provide uniformheating under very low loads with an even distribution of the heat. v

The various features of novelty which characterize this invention arepointed out with particularity in the claim annexed hereto and forming apart of this specification. For a better'understanding of the invention,however, its,

.advantages and specific objects obtained with its use, reference shouldbe had to the accompanying drawings Referring to the drawings, likenumerals identify similar parts throughout, and as will be seen fromFigure.

1, an embodiment of the'present invention may comprise a steam kettle 10of known construction having a steam jacket, 11 surrounding the kettle.This steamjacket has the drain or exhaust 12 at the bottom thereof,which is connected to the steam trap 13 and having the air exhaust line14a leading to the exhaust line 14. Air isadmitted through the supplyline 15, controlled by the valve 16, which may be of the manual type asshown, or be of a type to supply air at a constant pressure. This admitsthe air to the main supply conduit'16 and to the steam space between thejacket 11 and thekettle 10. A valve 18 is supplied. to permit a positive.shut-ofl'of the system when it is not in operation. Steam is'adrnittedthrough line 19 and controlled by the valve 20. I This valve may be ofthe manual type, as shown, or it may be controlled inch pressure to theline 17, the valve 18 is opened .and'

the valve 13 is so adjusted as to obtain'the desiredflow of airthroughthe space betweenthe kettle 10 the due to the flow of air. Thesteam source may be'of any convenient pressure such as 100 lbs.per-square inch where host a h u d have a te p ratu e neighborhood of 34"'n t'hoate P o o bei g ro g t into. loom W1 am and" t e eat is transf dom thof toa to the-a r. te m, ,-In t d fl w in heat, xch ng re ationsip. with the k tt e 0- ah Qt steam ltoprqduce a'heating of the kettlelly bel w those u a ly o F, fthe. advantage of uniform heat! ,re's wellasv atlower tempera,-

turf

at law.

1 M912! 7 ingat higher temperatures as well as at lower temperatures.This invention is not limited to heating within the ranges below 212 F.,but may be used for heating to higher temperatures, such as 212 F. to340 F., by simple regulation of the amount of steam that is admitted tothe air stream. This has not been possible using steam kettles where theamount of heat withdrawn from the surface 10 by the contents of thekettle was small, and the present system avoids the production of hotspots and the resulting damage to the contents of the kettle, v

The present system also has the advantages over the so-called vacuumsteam heating systems where pressures below atmospheric are used toproduce vapor having temperatures below 212 F. The obvious disadvantageof the vacuum steam heating system is the control of the flow of theheating fluid within the system. This disadvantage is overcome in thepresent invention by providing a positive control of flow of the heatingfluid due to the constant flow of air.

A second modification of this system isshown in Figure 2, wherein air isadmitted through the supply line 22 and controlled by the valve 23 andflows to the main supply line 24. The steam is admitted from the steamline 25 and is controlled by the valve 26 and flows to the main supplyline 24. The valve 27 controls the flow of steam and air to the heatingcoil 28 submerged within the kettle 29. The exhaust from the coil iscontrolled by the thermostat 31 to admit the proper amount of steamtoheatfthe coil to the desired temperature. In the above example a steamtrap has been shown. ,Any steam trap will work which will handle, asteady flow ofnon-con-c densable gas such as air inaddition to the steamand water contained therein. v f H While in 'the above embodiment ofthis invention steam has been used as .the source of heat,'and air atambient temperatures has been usedas a fluid to cause the steam to flowin the desired manner and to distribute the heat evenly over the heattransfer surface, other materials 00 one skilled in the art of'heating'. For exam'ple,. hydrocarbon gases may be used in the placeof air andmay be circulated in the usual manner; 'Diphenyl or other the usual:condensate separaton soth'at'the condensate may belreturned forreheating and the vapor recycled to Q I l carry the heated material intothe heat'tr'ansfer contact.

ill strated and describedgit will beappai'ent t0 hl fie It limite toheating Within, but m y be d r015 h in temperatures, such as 212 F. to840 F., by lation of the amount fst am t s dmitt d besides steam may beused, as.,wil1be apparent to materials maybeused as a heat carryingmedium in the V place ofsteam, and these materials may beseparated by Iskilled in the' art that changes may be made'in'the'form of theapparatus disclosed-i,without departing from the spirit of thisinvention as set forth in the appended claim, and that "in some casescertain feature's of; thisf'invention may be used to advantage withoutcorresponding'us e or other features. i

Whatis claimed is: f Apparatus for uniformly heating a heat sensitivematerial to within a predetermined temperature range, comprising: akettle having a chamber to contain such material, said chamber beingdefined bya Wall, an outer wall surrounding said chamber and formingbetween said Walls a restricted" passage having an inlet' and an outlet,

said passage being in heat exchange position relative to.

said chamber, means for supplying an' intermittent flow of steam underpressure to said restricted passage, said means introducing saidstreamdirectly against said charm; ber. wall and including a main,pipe'opening into said. passage at its inlet and a branch pipe connectedtosaid' steam under pressure, and means forsupplying' a constant stream,of air under pressure to the inlet of said restricted passage 'to'convey said steam' along saidpassage and.

produce aneven heating of the Walls of said passage over their entirelength includinga brench pipe connected to a- "source of air underpressure and also mnectea to said main pipe, and means for regulatingthe temperature of said mixture in said restricted passage, including athermostatically controlled steam regulating valve in the steam branchpipe and a thermostat to control said valve disposed in the heatexchange position relative to said steam at its point of entrance intosaid restricted passage, whereby said steam supply is so controlled asto prevent superheating of the walls of said restricted passage at thepointofentryfl. 1 'L ,1;

References Citedv in the file of this patent UNITED. SIAT PATENTS 48,839Rochow July 18, 1865 627,120 Jones June 20, 1899 833,271 Wentz Oct. 16,1906 1,150,439 Link Aug. 17, 1915 2,001,344 Fielder i May'14,'19352,102,106 Allen Dec. 14, 1937 2,277,944 Armstrong Mar. 31', 19422,371,807 Dalzell et a1. Mar. 20,1945 2,703,224 "Robinsoni'nu' Mar. 1,'1955 2,797,899 Funk et a1. July 2, 1957 mam

